CORROSION PROTECTION PROPERTIES OF POLYPYRROLE ELECTROPOLYMERISED ONTO STEEL IN THE PRESENCE OF SALICYLATE

M.B. GONZÁLEZ; S.B. SAIDMAN

PROGRESS IN ORGANIC COATINGS

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2012 vol. 75 p. 178 - 183

0300-9440

The corrosion performance of a polypyrrole coating constituted by hollow rectangular microtubes was monitored in chloride solutions using open circuit potential measurements, potentiostatic polarization and electrochemical impedance spectroscopy. The coating was electrosynthesized onto 316 L stainless steel from a salicylate solution and it provided a very good corrosion resistance to the substrate. It was found that polypyrrole films with granular morphology electrodeposited from a salicylate solution with ower concentration behave better in terms of protective behavior. In order to improve the corrosion protection imparted by the polypyrrole coating formed by the microtubes a system of two layers was electrodeposited, the first one consisted of polypyrrole with a granular morphology and the second one, on the top, was constituted by the microtubes. This bilayered system exhibited an excellent protective behavior during considerably long immersion time.